Bitcoin interest income

Notice 2014-21 says convertible virtual currency is property, and that virtual currency you receive as payment, including from mining, is ordinary income at fair market value when you receive it. That same value is your basis. A later sale or exchange is a capital gain or loss from that basis. BasisFix follows that shape for interest, mining, and referral payouts. The file it writes is a review with a tax pro, and the income lines are not on that form.

How the rows are labeled

Source row	BasisFix
River Account Activity, Interest Payout	Interest income. New lot at Fair Market Value USD.
River Bitcoin Activity, tag Interest	Interest income. New lot at USD Value.
River Mining Payout, or tag Mining	Mining income. New lot.
River Referral Reward, or tag Income	Referral, or “other” income on the Bitcoin Activity tag. New lot.
Cash App Boost or Bitcoin Boost	Ordinary income in the “other” category. BasisFix does not call a Boost interest.

Cash in and cash out, and an internal transfer of the same asset, do not open a lot and are not income. A send to your own wallet is not income either. It is a transfer, covered on River CSV to Form 8949.

Two moments, two forms

The day the coins arrive. Ordinary income at fair market value. BasisFix puts the amount on the income summary under interest, mining, referral, or other. It does not add a Form 8949 row.
The day you sell or spend them. Proceeds minus that fair market value, short-term or long-term from the payout date. That row is the Form 8949 candidate. The holding period starts at the payout, not at some earlier buy.

Skipping step 1 and then using zero basis on step 2 taxes the receipt and the sale as if they were one gain, and it puts income on the wrong form.

A missing price stays off the total

The invented River Account Activity file has interest of 40.00 included, and a second interest row with no fair market value. That second row opens a lot, is flagged, and is excluded from the income total. Mining on that fixture is 80.00 and the referral reward is 20.00. The invented Bitcoin Activity file has interest 8.50, mining 12.00, and other income 4.00. None of those numbers are on the Form 8949 worksheet. They are fixtures, not a rate River pays.

If your export has no USD column at all, the worksheet cannot look up a daily price. There is no price feed in this build. Supply the value on a generic row you are willing to defend, or leave the warning in place. See missing basis.

Questions

Does bitcoin interest go on Form 8949?

Not in BasisFix. Interest, mining, and referral payouts are ordinary income at fair market value. They are listed on the income summary. Form 8949 is for a later sale of those coins.

What is the basis of coins received as interest?

The fair market value you included as income. A later sale measures gain from that amount. Using zero would tax the same value twice.

What if the payout has no dollar value?

BasisFix still opens a lot and flags missing fair market value. The row is left out of the income total until a USD amount exists. It does not invent a price.